1. Field of the Invention
This invention relates to systems for back up control of a towed-vehicle and more particularly relates to controlling the pivot of a towed-vehicle's wheels.
2. Description of the Related Art
Presently there are several established methods of towing a motor vehicle. One method includes anchoring the motor vehicle to the top of a trailer and towing the trailer. For many common towing applications, such as towing a motor vehicle behind a motor home, the trailer method of towing a motor vehicle may not be practical due to the initial cost of purchasing the trailer, the trailer storage requirements, and the added weight of the trailer while towing. Additionally, the cost of maintaining the trailer to ensure safe operation may be prohibitively high. Because of the added weight of the trailer a more powerful and expensive towing vehicle may be required, and further costs may be incurred due to a decrease in fuel efficiency of the towing-vehicle.
Another method of towing a motor vehicle includes placing a tow dolly under the front wheels of the motor vehicle. While the tow dolly method may marginally decrease the costs and inconveniences of the trailer method, it doesn't eliminate them. For example, tow dollies may be expensive, heavy, inconvenient to store, and require maintenance. Another challenge of tow dollies is that great care must be taken when joining the tow dolly to the towing-vehicle and securing the towed-vehicle to the dolly. Failure to properly secure the towed-vehicle may result in severe safety and property issues. A properly secured towed-vehicle and tow dolly still provides driving and safety challenges to the driver of the towing-vehicle as the dolly may feel unstable while driving and be very difficult to back up.
A popular method for common motor vehicle towing applications is the tow bar. In contrast to trailers and tow dollies, tow bars are relatively inexpensive, easy to install, easy to store, and require little maintenance. The chief drawback of the tow bar is the inability of the towing vehicle to back up while towing without jackknifing with the towed-vehicle. Presently, if back up of the towing-vehicle using the tow bar is required then the towed-vehicle and the tow bar assembly must be removed, the towed-vehicle backed up separately, the towing-vehicle moved to the desired position, and then the towing vehicle and the tow bar assembly must be reconnected.